commit 5a924d156bc567a3319241645df700d6f4b9023f Author: aagbsn aagbsn@extc.org Date: Wed Aug 20 14:23:04 2014 +0000

Refactor Parasitictraceroute.

In particular, scapy.supersocket.L3RawSocket does not capture transmitted packets. --- ooni/nettests/experimental/parasitictraceroute.py | 13 +++++++----- ooni/utils/txscapy.py | 22 +++++++++++---------- 2 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/ooni/nettests/experimental/parasitictraceroute.py b/ooni/nettests/experimental/parasitictraceroute.py index 9526455..882d25a 100644 --- a/ooni/nettests/experimental/parasitictraceroute.py +++ b/ooni/nettests/experimental/parasitictraceroute.py @@ -1,5 +1,6 @@ from twisted.python import usage from twisted.internet import defer, reactor +from ooni.errors import handleAllFailures from ooni.templates import scapyt from ooni.utils import log from ooni.utils.txscapy import ParasiticTraceroute @@ -14,19 +15,23 @@ class ParasiticTracerouteTest(scapyt.BaseScapyTest):

samplePeriod = 40 requiresTor = False - requiresRoot = False

def setUp(self): self.report['parasitic_traceroute'] = {}

def test_parasitic_traceroute(self): self.pt = ParasiticTraceroute() + log.debug("Starting ParasiticTraceroute for up to %d hosts at inject " + "rate %d with %s" % (self.pt.numHosts, self.pt.rate, self.pt)) config.scapyFactory.registerProtocol(self.pt) d = defer.Deferred() - reactor.callLater(self.samplePeriod, d.callback, self.pt) + reactor.callLater(self.samplePeriod, d.callback, self) + d.addCallback(self.addToReport) + d.addErrback(handleAllFailures) return d

- def postProcessor(self, *args, **kwargs): + def addToReport(self, result): + log.debug("Stopping ParasiticTraceroute") self.pt.stopListening() self.report['received_packets'] = self.pt.received_packets

@@ -46,5 +51,3 @@ class ParasiticTracerouteTest(scapyt.BaseScapyTest): self.report['parasitic_traceroute'][p].sort(key=lambda x: x[0])

self.report['sent_packets'] = self.pt.sent_packets - return self.report - diff --git a/ooni/utils/txscapy.py b/ooni/utils/txscapy.py index ba90223..e8a27b6 100644 --- a/ooni/utils/txscapy.py +++ b/ooni/utils/txscapy.py @@ -160,7 +160,7 @@ class ScapyFactory(abstract.FileDescriptor): if not super_socket and sys.platform == 'darwin': super_socket = conf.L3socket(iface=interface, promisc=True, filter='') elif not super_socket: - super_socket = L3RawSocket(iface=interface, promisc=True) + super_socket = conf.L3socket(iface=interface)

self.protocols = [] fdesc._setCloseOnExec(super_socket.ins.fileno()) @@ -325,6 +325,8 @@ class ParasiticTraceroute(ScapyProtocol):

def sendPacket(self, packet): self.factory.send(packet) + self.sent_packets.append(packet) + log.debug("Sent packet to %s with ttl %d" % (packet.dst, packet.ttl))

def packetReceived(self, packet): try: @@ -332,24 +334,25 @@ class ParasiticTraceroute(ScapyProtocol): except IndexError: return

+ # Add TTL Expired responses. if isinstance(packet.getlayer(3), TCPerror): self.received_packets.append(packet) + # Live traceroute? + log.debug("%s replied with icmp-ttl-exceeded for %s" % (packet.src, packet[IPerror].dst)) return - elif packet.dst in self.hosts: if random.randint(1, 100) > self.rate: + # Don't send a packet this time return try: packet[IP].ttl = self.hosts[packet.dst]['ttl'].pop() del packet.chksum # XXX Why is this incorrect? - log.debug("Sent packet to %s with ttl %d" % (packet.dst, packet.ttl)) self.sendPacket(packet) k = (packet.id, packet[TCP].sport, packet[TCP].dport, packet[TCP].seq) self.matched_packets[k] = {'ttl': packet.ttl} return except IndexError: - pass - return + return

def maxttl(packet=None): if packet: @@ -369,17 +372,16 @@ class ParasiticTraceroute(ScapyProtocol):

self.hosts[packet.dst] = {'ttl': genttl()} log.debug("Tracing to %s" % packet.dst) - - elif packet.src not in self.hosts \ + return + if packet.src not in self.hosts \ and packet.src not in self.addresses \ and isinstance(packet.getlayer(1), TCP): - self.hosts[packet.src] = {'ttl': genttl(packet), 'ttl_max': maxttl(packet)} log.debug("Tracing to %s" % packet.src) - return + return

- elif packet.src in self.hosts and not 'ttl_max' in self.hosts[packet.src]: + if packet.src in self.hosts and not 'ttl_max' in self.hosts[packet.src]: self.hosts[packet.src]['ttl_max'] = ttl_max = maxttl(packet) log.debug("set ttl_max to %d for host %s" % (ttl_max, packet.src)) ttl = []